The purpose of this study is to test the adjuvant effect of FLT3 ligand. It is a recombinant human FLT3 ligand, a glycoprotein produced by recombinant DNA technology in a Chinese hamster ovary cell line. The ligand will be evaluated for safety when given subcutaneously to humans. The adjuvant effect will be monitored by immunizing with recombinant Hepatitis B vaccine. This will be an open label Phase I study